WAY too much grease on the hub. You just need a little bit on the inside of the spline area, it's doing nothing sitting on the face of the hub like that. The extra grease could have gotten onto the pressure plate, causing the disc to slip.

I second that too much grease for sure. Once your disc starts spinning all that goes out towards the clutch surface. I put a dab of never seize on the input shaft where the throw out bearing moves back and forth. That is all I do. That never spins.